If you are reading this article then you are probably diving into the world of infrared sauna research, and the deeper you dive the more confused you seem to get. Far Infrared, Mid Infrared, Near Infrared, Full Spectrum Infrared Saunas!? How is it possible to understand what’s what and make a sound decision when purchasing a sauna? And do I really need to spend big $$$ on a full spectrum infrared sauna?
At Sun Stream Saunas we understand why there is so much confusion, so please read on as we lay it all bare and make choosing the right sauna for you a whole lot easier!
Understanding Near Infrared, Mid Infrared and Far Infrared.
Infrared is divided into 3 segments, Near, Mid and Far Infrared, based on the length of the wavelengths. Some scientific literature uses the terms IR-A (Near Infrared), IR-B (Mid Infrared) and IR-C (Far Infrared). Of these, Far Infrared is the largest segment.
- Far Infrared Saunas (FIR) – 3,000nm – 1.0mm (3.0 microns – 1,000 microns)
- Mid Infrared (MIR) – 1400nm – 3000nm (1.4 microns- 3.0 microns)
- Near Infrared (NIR) – 780nm – 1400nm (.780 microns- 1.4 microns)
Infrared light is part of the spectrum emitted by the sun, which makes life possible on Earth. Sunlight is made up of ultraviolet (UV), visible light, and infrared light. All light is either reflected by, absorbed by, or transmitted through an object when it strikes it. In an infrared sauna, the object that the infrared light strikes is your body, and in order to generate heat in your body, the infrared light must be fully absorbed. Absorption of radiant energy is necessary to generate heat.
Far Infrared (FIR)
A Far Infrared Sauna emits a band of light we perceive as heat. We cannot see this band of light with the naked eye, but we can feel this type of light in the form of heat. We’ve all experienced the penetrating heat of an open fire on a cold night, or the heat of the sun’s rays on our body when a cloud moves away. The penetrating heat you feel is far infrared which has safely been used in infrared saunas for over four decades.
So how does a far infrared sauna work?
In a sauna application, far infrared (FIR aka IR-C) has a much higher absorption rate by water than does IR-B (Mid Infrared ) and IR-C (Near Infrared). Our skin is 80% water and thus Far Infrared from the sun, or that in an Infrared sauna, is highly absorbed in the layers of our skin and generates heat. This heat is then absorbed by the water content or moisture in our skin (1- 4mm depth) which is then drawn into deeper levels of our muscles and joints through conduction to induce a deep heavy sweat. Absorption is the key dynamic to generate heat in your body which is the primary purpose of a sauna.
All light when it hits an object, such as our body, is either absorbed, reflected or transmitted (passes through). FIR is highly absorbed, has a low reflection rate and a low transmission rate making it the best wavelength for the purposes of heating the human body. All carbon and ceramic based sauna heaters produce most of their energy in the FIR range.
Far infrared is the best wavelength for the purposes of a sauna; for a whole body radiant heat treatment, for raising your body’s core temperature, boosting your immune system and inducing a cleansing detoxing sweat.
Mid Infrared (MIR)
Mid Infrared (MIR aka IR-B) is not well studied and outside of the advertising from certain ‘full spectrum’ infrared sauna companies bragging about their heaters producing mid infrared, there does not seem to be any scientific literature explaining specific benefits of mid infrared which makes up a very small portion of the light spectrum (only 1.4- 3.0 microns). While mid infrared generates some heat in our body it is less effective at doing so compared to Far Infrared due to its lower rate of absorption.
The Ultra Low EMF & ELF Nano-Carbon panel heaters utilized in all Sun Stream infrared saunas emit far infrared (FIR) with approximately 70% of the heaters output lying between 5-15 microns (5000nm – 15000nm) and approximately 90% of the output lying between 1-20 microns (1000nm-20,000nm). Thus, our heaters also encompass the mid infrared range of 1.4- 3.0 microns.
Near Infrared (NIR)
Near Infrared (NIR aka IR-A) has a low absorption rate and a high reflection rate which means that emitters need to be placed in close proximity to the skin to overcome the skin’s natural defense mechanism. Once this is achieved NIR passes through our tissue where several biochemical reactions occur associated with cellular energy production and healing.
In contrast to far infrared, near infrared generates very little heat as it is transmitted through our tissue, its effects are biochemical, not thermal.
Since the 1960s, there is decades of research and now over 10,000 published studies on the therapeutic benefits of NIR and Red light which is known as Photobiomodulation Therapy (PBMT) or Low Level Light Therapy (LLLT) in the medical literature.
All PBMT/LLLT research has used either lasers or led sources of Red and NIR light. Single or dual frequencies of wavelengths in the visible Red 600nm range or invisible NIR in the 800nm range are the specific frequencies often used in the research. The research has discovered that our cells’ chromophores (light receptors) respond to a high intensity of a single or dual frequency in the 600nm or 800nm ranges.
Full Spectrum Infrared Saunas & Near Infrared Saunas | Marketing Vs Science
Unlike the far infrared emitting carbon and ceramic heaters used in most infrared saunas, some sauna companies use incandescent, halogen gas tube heaters and bulbs which emit visible light, near infrared, mid infrared and far infrared.
Full Spectrum Infrared Saunas | Halogen Heater Hazards
So-called “full spectrum” saunas have also created confusion in the market. Most infrared sauna manufacturers buy commercial saunas with quartz halogen tube heaters installed on the front wall of their far infrared saunas and call these saunas “full spectrum saunas.” Halogen tube heaters are used in many industrial drying applications and are often found in outdoor patio heaters. They are similar to heat bulbs in that they use a filament in an outer shell filled with halogen gas. Like heat bulbs, these “full spectrum” heaters radiate the entire infrared range (near, mid, and far), get very hot on their surface, and emit a significant amount of their energy in the form of visible light. Like heat bulbs, halogen tubes are not designed to produce far infrared, the wavelength scientifically considered to be most effective in warming the human body.
Both quartz halogen heaters and traditional heat lamp bulbs have entered the infrared sauna market, aiming to capitalize on the growing interest in Near Infrared and Red Light Therapy. The therapeutic use of Near Infrared and visible Red light has been widely studied since the 1960s. This treatment, known as Low Level Light Therapy (LLLT) or Photobiomodulation Therapy (PBMT), involves the use of lasers and LED devices to administer these specific light frequencies. In fact, Harvard Medical School even has a dedicated department focused on photomedicine.
Advocates of Full Spectrum and Near Infrared heat lamp saunas often reference the benefits shown in PBMT/LLLT studies, claiming that these same benefits can be achieved with their low-cost tube and bulb heaters. However, the Near Infrared light produced by these sauna devices differs significantly from that used in the studies. PBMT delivers light at a precise, single wavelength, intensity, and duration, providing a controlled “dose” of light energy. In contrast, PBMT treatments are typically brief, lasting only a few minutes, while an infrared sauna session usually lasts 30-45 minutes.
Skin risk hazards: Mounting common heat lamp bulbs or halogen tube heaters on the walls of a sauna may be a misguided design choice and pose potential risks to the skin. Research indicates that excessive exposure to Near Infrared (IR-A) light can cause “photoaging,” similar to the effects of UV radiation. Some studies even recommend that sunscreens protect against IR-A in addition to UV. Photoaging from Near Infrared exposure is well-documented, particularly on the faces of workers in high-heat environments like molten metal foundries and the arms of those working with large ovens (commonly known as “Baker’s Arm”). While Near Infrared light at a specific wavelength and short, controlled duration has several therapeutic benefits, prolonged exposure to Near Infrared emitted by tube heaters and bulbs in Full Spectrum and Near Infrared saunas—potentially used multiple times a week over many years—appears to be a poorly conceived and hazardous approach for sauna use.
- Near Infrared & Full Spectrum Sauna Dangers
- White Paper – A Look At The Science and Safety of Shortwave (NIR) Heat
EMF & ELF Exposure: The quartz halogen tube heaters used in so called ‘full spectrum saunas’ are not easily mitigated for EMF and ELF exposure, our testing indicates exposure of up to 12-20mG and in excess of 300v/m. Despite these readings companies are advertising their saunas as low EMF, but not disclosing the readings of their halogen tube heaters.
The Big Problem with Near Infrared Saunas!
Some sauna companies are using incandescent heat lamp bulbs, best known for warming food at fast food restaurants, for bathroom ceiling installations, or commonly found in chicken coups to warm young chicks. These common and inexpensive bulbs have been used to create saunas and proponents of their use have inaccurately termed these ‘Near Infrared’ saunas.
Although the manufacturers of these lamps (e.g., Sylvania and Philips) refer to these lamps as “near infrared” heat lamps, analysis of their spectral distribution curves shows that these lamps emit most of their energy in the mid-infrared region, with very little near infrared light (approximately 20%), a small amount of far infrared light, and a large amount of visible light. It is generally accepted that incandescent heat therapy has some benefits, but it does not meet the criteria for PBMT or LLLT.
Additionally, the glass bulbs of these lamps are very hot (approximately 4000°F) and have a significant warming effect on the air. The warming effect of these so-called “near infrared” saunas is not due to their near infrared output. As mentioned above, near infrared has low absorptivity and high reflectivity, and does not produce much heat in our bodies. It appears that users of heat lamp saunas warm their bodies with less efficient mid-infrared light, and simply warm the air in the small canvas tents that are typically used in these saunas. Since near infrared does not produce much heat in our bodies, we have always considered the term “near infrared” sauna to be an oxymoron, and proponents of these saunas have created great confusion in the infrared sauna market.
Noteworthy to is the fact that it is nearly impossible to get close enough to these very hot lamps due to the extremely high surface temperatures. On the other hand, to achieve adequate levels of near-infrared energy, lasers and LEDs can produce the single-frequency wavelengths required for treatment and can be conveniently placed close enough to the body, even directly pressed against the skin, to ensure that therapeutic amounts of light energy are delivered.
Conclusion: A “Near Infrared Sauna” is a contradiction of terms. The primary function of a sauna is to generate heat in your body to raise your core temperature, boost your immune system and induce a heavy sweat. Near infrared generates very little heat in your body as it passes through our tissue and does not serve the hyperthermic purpose of sauna.
Don’t Be Deceived By The Marketing Hype Of So Called ‘Full Spectrum Infrared Saunas’ and ‘Near Infrared’ Saunas!
As we have learnt some sauna companies are recommending the use of common near infrared heat lamps or quartz halogen tube heaters for NIR therapy purposes. These devices are extremely hot and it is impossible to place your skin close enough to the bulbs to receive therapeutic levels of NIR without getting burnt.
Both of these devices emit over a wide range of frequencies covering visible light, near, mid, and far infrared. They do not emit a high level of Red or NIR energy at a single frequency as the medical research has determined to be necessary to stimulate our cells’ light receptors.
LEDS, on the other hand, DO NOT emit dangerous levels of heat and can be placed close to or even directly on our skin to ensure that therapeutic levels of the NIR light are transmitted into our tissue.
For supporting evidence please read the following blog posts from infrared sauna experts Matt Justice and Alex Fergus:
Add-On The Ultimate Full Spectrum Experience To Your Sun Stream Infrared Sauna
Since the introduction of so called ‘Full Spectrum’ infrared saunas and near infrared saunas’ into the market place, people genuinely searching for the best sauna have become confused, frustrated and in many cases misled by false marketing claims all in the name of science.
At Sun Stream Saunas we felt it was necessary to end the confusion by producing authentic science based near infrared and red light therapy panels that deliver a therapeutic dose of light energy.
Our ROJO Red light therapy panels are the best on the Australian market. Experience five of the most clinically relevant wavelengths of RED 630nm/660nm and near infrared 810nm/830nm/850nm for maximum healing benefits.
High quality drivers and components reduce the damaging effects of EMF/ELF and Flicker to near zero levels.
To learn more view our Rojo red light therapy page or contact us with your list of questions.